Motor vehicle occupancy and high temperature alarm module

ABSTRACT

A machine to turn on the occupancy sensor(s) of a motor vehicle using a temperature sensing element. The temperature element senses a dangerously high temperature in the passenger compartment of a motor vehicle and energizes the occupancy sensors. The occupancy sensors energize for a time period sufficient to determine the presence or absence of an occupant. If no occupant is detected, the occupancy sensors de-energize after a set period of time. If an occupant is detected, an audible alarm is enabled to draw attention to the motor vehicle. Once the alarm is active, a key must be used to reset it. If no occupant is detected each operation of a door switch will cause an additional sensing provided the temperature remains dangerously high. This logic is only energized or enabled when a passenger compartment is dangerously high.

This application is a Continuation of U.S. application Ser. No.09/940,150 filed Aug. 27, 2000 now U.S. Pat. No. 6,737,975, thespecification of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

This invention relates generally to the field of devices for detectingthe presence of an occupant present in an motor vehicle passengercompartment, and more particularly, the detection of a dangerously hightemperature, controlled by logical conditions to activate an audiblealarm.

Occupancy sensors are known, and vary in many varieties and varyingcomplexity, such as within the confines of motor vehicles.

An occupancy sensor that is typical of the prior art is disclosed inU.S. Pat. No. 6,270,116 This prior art occupancy sensor consists of anapparatus which detects electromagnetic radiation above the seat, and aprocessor determines the presence of an occupying item, based on thedetected electromagnetic radiation and is distinguished betweendifferent occupying items to thereby obtain information about theoccupancy of the seat. An apparatus for controlling a deployableoccupant restraint device in a vehicle to protect the occupant in theseat of the vehicle during a crash includes the evaluating apparatus andthe processor further affects the deployment of the occupant restraintdevice based on the determined presence or absence of an occupying itemand the information obtained by the occupancy of the seat.

Another occupancy sensor that is typical of the prior art is a seatswitch and a seatbelt switch requiring a lesser degree of complexity.

Yet another occupancy sensor is an audio pickup and an amplifier thatwould turn on to amplify a baby's cries or children's sounds to anoutside speaker to bring attention to the motor vehicle, acting as analarm.

SUMMARY OF THE INVENTION

The primary object of the invention is To use the controlled output ofan occupancy sensor like or similar to those previously described,together with a temperature element to activate an audible alarm. Whenan occupant is detected by the occupancy sensor and a dangerously hightemperature exists in the passenger compartment (may include the trunkarea) of the motor vehicle an audible alarm is activated. Another objectof the invention is To provide a method to energize the occupancysensor(s) for a period of time, only long enough to determine theabsence or presence of an occupant and then enter a “sleep mode” andshut down the occupancy sensor(s) to conserve power when the motorvehicle is not in use. Another object of the invention is To provide amethod to re-energize the occupancy sensors after the “sleep mode” hasturned them off with the operation of a door switch.

A further object of the invention is To provide a period of time, whenthe vehicle is not in use, for the occupancy sensors to power up, warmup, and stabilize their output(s) before these output(s) can activate analarm.

Yet another object of the invention is To provide logic allowing theoccupancy sensor(s) power to be connected and controlled at a singleelectrical termination whether the vehicle is in or is not in use.

Still yet another object of the invention is To provide an alarm resetsequence, whereby only a key holder for the vehicle can reset the alarmonce an alarm condition is activated.

Other objects and advantages of the present invention will becomeapparent from the following descriptions, taken in connection with theaccompanying drawings, wherein, by way of illustration and example, anembodiment of the present invention is disclosed.

A machine for combining the output of an occupancy sensor and atemperature sensing element comprising: a logical network of timers,switches, relays and interconnections by methods of relay logic, ladderlogic, Boolean logic operators, software algorithms, or a combination ofany or all of the above mentioned methods, to produce a reliableactivation of an audible alarm. If an occupant is detected in a motorvehicle's passenger compartment when the vehicle is not in use, and adangerously high temperature exists in the passenger compartment, anaudible alarm is activated.

The drawings constitute a part of this specification and includeexemplary embodiments to the invention, which may be embodied in variousforms. It is to be understood that in some instances various aspects ofthe invention may be shown exaggerated or enlarged to facilitate anunderstanding of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the invention.

FIG. 2 is a detailed view of the logical network of timers, switches,relays and interconnections as one method to demonstrate operation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Detailed descriptions of the preferred embodiment are provided herein.It is to be understood, however, that the present invention may beembodied in various forms. Therefore, specific details disclosed hereinare not to be interpreted as limiting, but rather as a basis for theclaims and as a representative basis for teaching one skilled in the artto employ the present invention in virtually any appropriately detailedsystem, structure or manner.

As illustrated in FIG. 1, a microprocessor receives initial power upthrough a temperature switch. Additional inputs are received fromoccupancy sensor(s), the ignition switch, and passenger door switches. Atest switch is included but may or may not be remotely located.

As illustrated in FIG. 2 the microprocessor contains symbols ofalgorithms performing the functional logic of timers and relays withtheir assigned interconnections. The following described steps are usedto demonstrate the various logical tasks incorporated in this machine.

A key switch and an ignition switch are the same device.

-   STEP 1. The logic module will operate on the vehicle's 12VDC battery    power but in future models, a lower voltage for logic state    indication to Boolean logic operators or a result of other software    algorithms may be used or a combination thereof.-   STEP 2. A temperature sensitive switch “A” interrupts the power or    logic to the occupancy sensor until such time the passenger    compartment exceeds a preset level. When this level is exceeded,    power is supplied to the normally closed key switch relay contact    “B”. This temperature sensing element might be a bi-metalic switch,    an RTD circuit, a thermocouple circuit, or any type device that    could be made to conduct or operate as a switch at a specific    temperature.-   STEP 3. The power will then pass through the normally closed key    switch relay contact “B”, which is closed when the key switch is in    the “OFF” position. When the key switch is on, power to this logic    is interrupted.-   STEP 4. With a high temperature in the passenger compartment, and    the key switch relay in the “OFF” position, power is supplied to the    stability timer “C”, the sample minutes timer “T”; by means of the    normally closed toggle relay contact “AA”; and to the occupancy    sensors “D” through the normally closed TMR1 contact “KK” and the    key switch relay contact “EE”. With the toggle switch relay contact    “AA” closed and the seal-in contact “I” closed, the total minutes    timer “T” begins timing the total sense time. The stability timer    “C”, begins timing a delay on that interrupts power to the alarm    circuits with its normally open contact “F”. The occupancy sensor is    on and warming up to assume a logical state and allows for occupants    to enter or exit before permitting STEP 5.-   STEP 5. When the stability timer period is complete, the stability    timer contact “F”, closes to energize the remaining components of    the alarm control circuits.-   STEP 6. When the occupancy sensor detects an occupant, and the    previously mentioned conditions remain true, the occupancy sensor    logic output for this condition is fed to the ALM relay coil “BB”.    Its normally open contact “G” will close allowing power to travel to    the normally closed contact of TMR4 “P” and then to the coil of TMR3    “U”.-   OPTION: An analog input element “DD” could be used to convert a    standard signal, like 4-20 milliamperes or 0-10VDC etc., to compare    with a threshold level quantity representing an occupant is    detected, and provide a logic output to the ALM relay “BB”. The    preferred operation is to operate the ALM relay with a digital    output from the occupancy sensor(s) for ease of standardization and    to promote this as an industry standard. (shown in dashed lines)-   STEP 7. TMR3 “U” begins to count for a preset period and when it is    reached, the normally open contact TMR3 “H” closes and allows power    to the audible alarm device “Q”. At the same time, the normally open    contact of TMR3 “J” closes and energizes the seal-in relay “K”. The    seal-in relay contact “L” closes, and through the normally closed    contact of the key switch relay “M”, latches the seal-in relay on.    Another seal-in relay contact “N” now sustains the alarm condition    provided by the occupancy sensors, insuring the alarm condition    remains until responsible human intervention cancels the alarm.-   STEP 8. The horn is now on, and at the same time, TMR4 “O” begins to    time its preset interval. When complete, the normally closed contact    of TMR4, “P” opens, resetting timer TMR3, opening TMR3's contact    “H”, causing the horn “Q” to turn off for a period and in the same    instant, resets TMR4 closing TMR4's contact, “P” until TMR3 times    its interval once again, and closes its contact “H” sounding the    horn again. These interval times can be adjustable. The horn turns    on, then off, until the alarm is reset by turning the key switch “Z”    to the on position, energizing the key switch relay “R”, opening key    switch relay contact “M”, de-energizing (resetting) the seal-in    relay “K”, the stability timer “C” and the total minutes timer “T”.    With the operation of the key switch, the stability timer is reset    by the key switch relay contact “B”, allowing time for the passenger    to enter and start the motor vehicle or exit the motor vehicle    before arming the alarm. The toggle relay contact “AA” is bypassed    when there is an alarm condition so the door switch can not reset    the alarm with seal-in relay contact “HH”.-   STEP 9. Door switch “S” operates toggle relay “GG”. When the    passenger compartment door is opened, door switch “S” closes and    energizes the toggle relay (dome light on) to open the normally    closed contact “AA”, and resets TMR1 timer closing TMR1 contact “E”,    and resets the stability timer, restarting the occupant warm up and    sense cycle. When the sample minutes timer completes its timing,    power is removed from the occupancy sensors and other elements when    no occupant is detected. The normally closed contact of TMR1 “E”    opens, resetting TMR2, opening stability timer contact “F”. Power to    the occupancy detector(s) remain interrupted until a door is opened    and dosed again, the temperature switch opens then closes, or the    key switch is turned on then off resetting TMR1 and TMR2 for another    occupancy check. If no occupant is detected, the occupancy detectors    are turned off to conserve power. In an alarm condition, normally    closed seal-in relay contact “I” opens to reset TMR1, holding it off    and it cannot enter the sleep mode. Normal sample minutes timer    operation resumes when the alarm condition is cleared.-   STEP 10. A system test is accomplished by depressing pushbutton test    switch “V”, with the key switch in the on position energizing the    key switch relay, closing the key switch relay contact “CC”. This    energizes test relay “W”, closing test relay contact “X” to simulate    a passenger compartment high temperature and the key switch is in    the off position; and test relay contact “Y” to simulate the    occupancy sensor detects an occupant. The test relay will not latch    the seal in relay because the normally closed key switch relay    contact “M” is now open. The test relay will latch itself with    contact “II” to allow TMR1 and TMR2 to sequence an alarm. The test    mode ends when the horn is activated one time and TMR4 opens its    contact “JJ” resetting the test relay latch or when the key switch    is turned off, disabling the test mode. A test cannot begin unless a    key holder has the key switch in the on position. The key switch    refers to the ignition switch in all references.-   STEP 11. With the key switch not in the off position, normally open    key switch relay contact “FF” closes to provide power to the    occupancy sensors while driving the car. This eliminates the need    for a separate power source when installing this unit with the    occupancy sensor. At the same time, the normally closed key switch    relay contact “EE” opens and prevents back feeding power to the    control circuits, keeping this supply point isolated until the key    switch is turned off.

1. An apparatus for monitoring a vehicle compartment, comprising: anoccupancy sensor for generating a first signal indicative of thecompartment being occupied; a temperature element for generating asecond signal indicative of a vehicle compartment ambient temperatureexceeding a preset limit; and a logic circuit for generating an alarmsignal responsive to the first and second signals being generated duringa sampling period, wherein the sampling period is initiated afterexpiration of a delay period following each simultaneous occurrence ofan indication of a closed vehicle door and the second signal beinggenerated.
 2. The apparatus of claim 1, wherein the occupancy sensor isactivated when the sampling period is initiated.
 3. The apparatus ofclaim 1, wherein the sampling period is reset and initiated afterexpiration of a delay period following each simultaneous occurrence ofan indication of a closed vehicle door, a vehicle being off, and thesecond signal being generated.
 4. The apparatus of claim 1, wherein theoccupancy sensor is energized and communicatively coupled to an occupantrestraint control system when a vehicle is off.
 5. The apparatus ofclaim 1, wherein the occupancy sensor is energized and communicativelycoupled to an occupant restraint control system when a vehicle is on. 6.The apparatus of claim 1, wherein the sampling period ends a preset timeafter it is initiated.
 7. The apparatus of claim 1, further includingmeans for resetting to reset the alarm signal, wherein after the alarmsignal is generated, the logic circuit seals-in the alarm signal untilinterrupted by the means for resetting.
 8. A system for monitoring avehicle having a compartment, comprising: an occupancy sensor forsensing whether the compartment is occupied; a temperature sensor formeasuring a vehicle compartment ambient temperature; a logic componentconnected to the occupancy sensor and the temperature sensor todetermine whether to initiate an alarm based upon information receivedfrom the occupancy and temperature sensors; an alarm component connectedto the logic component for producing an alarm when initiated by thelogic component; and a vehicle door sensor to indicate an open/closedcondition of a vehicle door, wherein the logic component includes asampling period that is initiated after each simultaneous occurrence ofthe occupancy sensor indicating the vehicle is occupied, the vehicledoor sensor indicating that a vehicle door condition has changed betweenopen and closed, and the temperature sensor indicating a temperatureexceeding a preset limit.
 9. The system of claim 8, wherein thecompartment is a trunk.
 10. The system of claim 8, further including anignition sensor to indicate an on/off condition of the vehicle andwherein the logic component includes a sampling period that is reset andinitiated after each simultaneous occurrence of the occupancy sensorindicating the vehicle is occupied, the ignition sensor indicating thatthe vehicle is off, and the temperature sensor indicating a temperatureexceeding a preset limit.
 11. The system of claim 8, further including avehicle door sensor to indicate an open/closed condition of a vehicledoor and wherein the logic component includes a sampling period that isreset and initiated after each simultaneous occurrence of the occupancysensor indicating the vehicle is occupied, the vehicle door sensorindicating that a vehicle door is closed, and the temperature sensorindicating a temperature exceeding a preset limit.
 12. The system ofclaim 8, wherein the occupancy sensor senses whether a seat within thecompartment is occupied.
 13. The system of claim 8, further comprising ameans for testing the system by generating a set of conditions that willcause the logic component to initiate the audible alarm.
 14. A method ofmonitoring a vehicle having a compartment, comprising: generating afirst signal indicative of the compartment being occupied; generating asecond signal indicative of a vehicle compartment ambient temperatureexceeding a preset limit; and generating an alarm signal responsive tothe first and second signals being generated during a sampling period,wherein the sampling period is initiated after expiration of a delayperiod following each simultaneous occurrence of an indication of aclosed vehicle door and the second signal generated.
 15. The method ofclaim 14, further including activating at least one occupancy sensorwhen the second signal is generated.
 16. The method of claim 14, furtherincluding resetting the sampling period when the vehicle is indicated asbeing on.
 17. The method of claim 14, further including resetting thesampling period when a vehicle door is indicated as being open.
 18. Anapparatus, comprising: an occupancy component for generating a firstsignal indicative of a vehicle compartment being occupied; a temperaturecomponent for generating a second signal indicative of a vehiclecompartment ambient temperature exceeding a preset limit; a logiccomponent for generating an alarm signal responsive to the first andsecond signals being generated; and a delay component that delays thegeneration of the alarm for a period of time upon an indication of avehicle door closing; wherein the period of time is initiated after eachsimultaneous occurrence of an indication of a closed vehicle door andthe second signal being generated.
 19. The apparatus of claim 18,wherein at least two of the occupancy, temperature, logic, and delaycomponents are combined in a single electrical circuit.
 20. Theapparatus of claim 18, wherein the logic component is enabled inresponse to the second signal being generated.
 21. The apparatus ofclaim 18, wherein the logic component generates the audible alarm signalresponsive to the first and second signals being generated during asampling period.
 22. The apparatus of claim 21, wherein the samplingperiod is expired, the occupancy sensor is disabled.
 23. The apparatusof claim 21, wherein the sampling period is initiated when the secondsignal is generated.
 24. The apparatus of claim 21, wherein the samplingperiod is ended if the period ends without the simultaneous occurrenceof an indication of a closed vehicle door and the second signal beinggenerated.
 25. An apparatus for monitoring a vehicle compartment,comprising: an occupancy component for generating a first signalindicative of the compartment being occupied; a temperature componentfor generating a second signal indicative of a vehicle compartmentambient temperature exceeding a preset limit; and a logic component forgenerating an alarm signal responsive to the first and second signalsbeing generated during a sampling period, wherein the sampling period isinitiated after each simultaneous occurrence of an indication of aclosed vehicle door and the second signal being generated.
 26. Theapparatus of claim 25, wherein the temperature component generates asecond signal when the vehicle compartment ambient temperature exceeds ahigh temperature limit.
 27. The apparatus of claim 25, wherein thetemperature component generates a second signal when the vehiclecompartment ambient temperature exceeds a low temperature limit.